Organic Molecules:
DNA and Proteins
Four Types of Macromolecules and their
Monomers:
1.
Lipids – Fatty acids and glycerol
2.
Carbohydrates – Monosaccharide
3.
Nucleic Acids – Nucleotide
4.
Protein – Amino Acids
(not really the monomer)
Nucleic Acids
 Two
types of
nucleic acids:
 DNA
–
Deoxyribonucleic
Acid
 RNA
–
Ribonucleic Acid
Nucleic Acids
 REMEMBER:
the monomer of nucleic
acids is a nucleotide.
 Nucleotides
 Phosphate
 5-carbon
consist of three parts:
group
sugar
DNA
– Deoxyribose
RNA
– Ribose
 Nitrogenous
bases
DNA
– Adenine, Thymine, Cytosine,
Guanine
RNA
– Adenine, Uracil, Cytosine, Guanine
Nucleic Acids
 Due
to nucleotides
coming in four different
varieties or “flavors”,
RNA and DNA can code
for a wide variety of
proteins that spell out
how an organism is
formed and survives.
 DNA
and RNA encode
genetic information.
DNA vs. RNA
RNA
DNA

DNA’s 5-carbon sugar
is deoxyribose.

RNA’s 5-carbon sugar
is ribose.

DNA Base Pairs:

RNA Base Pairs:
 Adenine
– Thymine
 Adenine
– Uracil
 Guanine
– Cytosine
 Guanine
– Cytosine
 Double
stranded

Single stranded
Nucleic Acid
 Nucleic
acid chains
(polymers) are made by
joining the phosphate group
of one nucleotide to the
sugar of a second
nucleotide.
 The phosphate group and
sugar form the backbone of
the nucleic acid chain.
nitrogenous base are
not involved in the
forming the chain.
Nucleotide
 The
Nitrogenous Base
Nucleic Acid
 The
nitrogenous bases bond the two
separate strands with hydrogen
bonds.
 For
this to occur, the two nucleic acid
strands must be complementary to
each other.
 Each
type of nucleotide must pair
with its partner type on the other
strand:
Adenine
bonds with Thymine (A-T)
Guanine
bonds with Cytosine (G-C)
Nucleic Acid Functions
 Encoding
Genetic Material: Genes
found in DNA provide specific
instructions for making proteins the
organism needs to carry on life
functions.
 Protein
Synthesis: RNA transport
genetic messages to the ribosomes
to produce proteins.
 Composing
Ribosomes – Ribosomes
are composed of RNA and proteins.
Nucleic Acid Think About
 Which
is not found in both RNA and
DNA?
a.
Ribose sugar
b.
Phosphate group
c.
Nitrogenous base
d.
Guanine nucleotide
Proteins
 Proteins
are important
polymers that perform
structural and regulatory
functions for the cell.
 Proteins
are macromolecules
that consist of long chains of
amino acids (monomer).
 Long
chains of amino acids
are called polypeptide
chains.
Proteins
acids are all
composed of the same
amino, carboxyl and
central carbon structure.
Central Carbon
 Amino
 The
difference between
amino acid monomers is due
to each amino acid having a
different R group.
 There
are 20 different R
groups that make 20
different amino acids.
Amino
Carboxyl Group
Proteins
 Peptide
bonds join
amino acids through
dehydration synthesis
reactions.
 Long
polypeptide
chains are formed
from this process,
which connects
hundreds of amino
acids together.
Protein Functions
 Cell
Structure: they make most
of the structure in the cell
including the cytoskeleton.
 Animal
Structures: they make
up bones, muscle, tendons and
hair.
 Cell
Function: they help control
what enters and leaves through
the cell membrane.
 Enzymes:
speed up chemical
reactions in cells and organisms.
Nucleic Acid / Protein
Review
Which term refers to this
molecule?
a.
Nucleotide
b.
Amino acid
c.
Polypeptide
d.
Nitrogen base
Nucleic Acid / Protein
Review
Which pair of terms is NOT
correctly matched?
a.
Deoxyribose : RNA
b.
Polypeptide : Protein
c.
Nitrogenous base: DNA
d.
Amino acid : Polypeptide
Nucleic Acid / Protein
Review
Which does NOT describe a function of
proteins?
a.
They encode genetic information
b.
They allow muscle cells to contract.
c.
They help to carry out chemical reactions.
d.
They make up structures that support the
cell.